• Title/Summary/Keyword: Emerged Plants

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ARISING TECHNICAL ISSUES IN THE DEVELOPMENT OF A TRANSPORTATION AND STORAGE SYSTEM OF SPENT NUCLEAR FUEL IN KOREA

  • Yoo, Jeong-Hyoun;Choi, Woo-Seok;Lee, Sang-Hoon;Seo, Ki-Seog
    • Nuclear Engineering and Technology
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    • v.43 no.5
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    • pp.413-420
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    • 2011
  • In Korea, although the concept of dry storage system for PWR spent fuels first emerged in the early 1990s, wet storage inside nuclear reactor buildings remains the dominant storage paradigm. Furthermore, as the amount of discharged fuel from nuclear power plants increases, nuclear power plants are confronted with the problem of meeting storage capacity demand. Various measures have been taken to resolve this problem. Dry storage systems along with transportation of spent fuel either on-site or off-site are regarded as the most feasible measure. In order to develop dry storage and transportation system safety analyses, development of design techniques, full scale performance tests, and research on key material degradation should be conducted. This paper deals with two topics, structural analysis methodology to assess cumulative damage to transportation packages and the effects of an aircraft engine crash on a dual purpose cask. These newly emerging issues are selected from among the many technical issues related to the development of transportation and storage systems of spent fuels. In the design process, appropriate analytical methods, procedures, and tools are used in conjunction with a suitably selected test procedure and assumptions such as jet engine simulation for postulated design events and a beyond design basis accident.

Development of Revegetation Method Using Forest Topsoils for Ecological Restoration of the Slopes(I) (산림표층토를 활용한 비탈면 생태복원녹화에 관한 연구(I))

  • Nam, Sang-Jun;Yeo, Hwan-Joo;Choi, Jae Yong;Kim, Namchoon
    • Journal of the Korean Society of Environmental Restoration Technology
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    • v.7 no.4
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    • pp.110-119
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    • 2004
  • This research was conducted to develop spraying cultivation method using forest topsoils in order to restore the disturbed slopes. In November the researcher collected a depth of 5 cm of topsoils from a well developed forest, after the fallen leaves were cleared. The essential results of the research are as follows: In the case of using the forest topsoils, during the early stages of planting, time is necessary for the desired vegetation to reach a similar state to the vegetation being restored. The best possible effect is obtained through a method utilizing forest topsoil(30%)+loam silt soil(70%)+seeding with grasses and native plants including trees, shrubs, and herbs. Several plants such as Pinus densiftora, Potentilla fragarioides, Miscanthus sinensis, Erigeron canadensis seemed to be naturally emerged from the topsoils From this experiment, it was recommended that environment potential within topsoil should be comprehended. Also, topsoil deposit and gathering methods should be experimented properly.

Application of Jasmonic Acid Followed by Salicylic Acid Inhibits Cucumber mosaic virus Replication

  • Luo, Ying;Shang, Jing;Zhao, Pingping;Xi, Dehui;Yuan, Shu;Lin, Honghui
    • The Plant Pathology Journal
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    • v.27 no.1
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    • pp.53-58
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    • 2011
  • Systemic acquired resistance is a form of inducible resistance that is triggered in systemic healthy tissues of local-infected plants. Several candidate signaling molecules emerged in the past two years, including the methylated derivatives of well-known defense hormones salicylic acid (SA) and jasmonic acid (JA). In our present study, the symptom on Cucumber mosaic virus (CMV) infected Arabidopsis leaves in 0.1 mM SA or 0.06 mM JA pre-treated plants was lighter (less reactive oxygen species accumulation and less oxidative damages) than that of the control group. JA followed by SA (JA${\rightarrow}$SA) had the highest inhibitory efficiency to CMV replication, higher than JA and SA simultaneous co-pretreatment (JA+SA), and higher than a JA or a SA single pretreatment. The crosstalk between the two hormones was further investigated at the transcriptional levels of pathogenesis-related genes. The time-course measurement showed JA might play a more important role in the interaction between JA and SA.

Failure Evaluation Plan of a Reactor Internal Components of a Decommissioned Plant

  • Hwang, Seong Sik;Kim, Sung Woo;Choi, Min Jae;Cho, Sung Hwan;Kim, Dong Jin
    • Corrosion Science and Technology
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    • v.20 no.4
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    • pp.189-195
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    • 2021
  • A technology for designing and licensing a dedicated radiation shielding facility needs to be developed for safe and efficient operation an R&D center. Technology development is important for smooth operation of such facilities. Causes of damage to internal structures (such as baffle former bolt (BFB) of pressurized water reactor) of a nuclear power reactor should be analyzed along with prevention and countermeasures for similar cases of other plants. It is important to develop technologies that can comprehensively analyze various characteristics of internal structures of long term operated reactors. In high-temperature, high-pressure operating environment of nuclear power plants, cases of BFB cracks caused by irradiated assisted stress corrosion cracks (IASCC) have been reported overseas. The integrity of a reactor's internal structure has emerged as an important issue. Identifying the cause of the defect is requested by the Korean regulatory agency. It is also important to secure a foundation for testing technology to demonstrate the operating environment for medium-level irradiated testing materials. The demonstration testing facility can be used for research on material utilization of the plant, which might have highest fluence on the internal structure of a reactor globally.

Back to Nature-Based Agriculture: Green Livelihoods Are Taking Root in the Mekong River Delta

  • Lan, Ngo Thi Phuong;Kien, Nguyen Van
    • Journal of People, Plants, and Environment
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    • v.24 no.6
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    • pp.551-561
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    • 2021
  • Background and objective: Vietnam is prioritizing agricultural production for food export capacity in all national policies. As a result, for three decades, its agriculture has been making quite many remarkable achievements. Methods: The most successful one is that the nation has become one of the world's leading rice exporters and ensures its national food security. Through these endeavors, the Mekong River Delta (MRD), in particular, has emerged as a key region in ensuring national food security and rice export. Results: The new era can now see Vietnamese agriculture turning to place special emphasis on commodity quality and the improvement of the living environment. This is evidenced, for example, by the phenomenon that the MRD, as a rice basket of the whole country, is making moves back to nature-based agriculture with attempts to restore the natural ecology, including preserving and restoring local traditional rice seeds, adopting natural farming practices and minimizing the use of chemical fertilizers and pesticides. Conclusion: The case studies of nature-based farming practices in the MRD indicate that, while the national agriculture is generally developing large-scale production, the small-scale farming in the region, integrated with tourist and educational activities on-site, is meeting the demands of a highly potential domestic niche market. Moreover, this model appears to be a sustainable farming approach that defines itself as a working green livelihood for the region.

Natural Products as Potential Therapeutic Strategies for Parkinson's Disease

  • Hae-Rim Cha;Mi-Ran Lee;Hyun-Jeong Cho
    • Biomedical Science Letters
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    • v.29 no.3
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    • pp.121-129
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    • 2023
  • Parkinson's disease (PD) is a progressive neurodegenerative disorder that affects millions of people worldwide. The conventional treatment model for PD have harmful side effects, such as dyskinesia, hallucinations, nausea, and fatigue, and are expensive. As a result, natural products derived from medicinal herbs, fruits, and vegetables have emerged as potential therapeutic strategies for PD. These natural products have been traditionally used to treat various diseases and have been shown to possess anti-oxidative and anti-inflammatory properties, as well as inhibitory roles in protein misfolding, mitochondrial homeostasis, neuroinflammation and other neuroprotective processes. In addition, they have fewer side effects and are generally less expensive than conventional drugs. It also discusses the limitations of current treatments and the potential of natural remedies derived from plants to treat PD in new ways or as supplements to existing treatments. The multifunctional mechanisms of medicinal plants that may be utilized to treat PD are also discussed, including the modulation of neurotransmitter systems, the enhancement of neurotrophic factors, and the inhibition of apoptosis. While more research is needed to fully understand their mechanisms of action and efficacy, natural products have the potential to provide safer and more effective treatment options for patients with PD.

Flora in Ahnshim Wetland, Daegu Metropolitan City (대구광역시 안심습지의 식물상)

  • You, Ju-Han;Jung, Sung-Gwan;Park, Kyung-Hun;Kim, Kyung-Tae;Lee, Woo-Sung
    • Korean Journal of Plant Resources
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    • v.21 no.2
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    • pp.162-170
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    • 2008
  • The purpose of this study was to suggest the raw data on establishing the domestic wetland conservation plan. The results of this study were as follows. The vascular plants were summarized as 201 taxa in Ahnshim wetland; 57 families, 154 genera, 179 species and 22 varieties. The rare and endangered plant designated by Korea Forest Service was Hydorcharis dubia. In the wetland plants, the emerged plants were showed Typha angustata, Beckmannia syzigachne, Zizania latifolia, Phragmites communis, Persicaria thunbergii, Oenanthe javanica and Veronica undulata, and the submerged plants were Potamogeton crispus, Vallisneria asiatica, Hydrilla verticillata, Ceratophyllum demersum and Myriophyllum verticillatum. And the floating leaved plants were confirmed Potamogeton distinctus, Hydrocharis dubia, Nelumbo nucifera and Nymphoides peltata, and the floating plants were Salvinia natans, Spirodela polyrhiza and Lemna paucicostata. The naturalized plants were 33 taxa; Avena fatua, Dactylis glomerata, Rumex crispus, Rumex conglomeratus, Amaranthus retroflexus, Lepidium apetalum, Tlaspi arvense, Descurainia pinnata, Potentilla supina, Vicia villosa, Robinia pseruo-acacia, Amorpha fruticosa, Trifolium repens, Medicago sativa, Ailanthus altissima, Euphorbia supina, Oenothera lamarckiana, Quamoclit angulata, Ipomoea purpurea, Solanum nigrum, Veronica perisca, Helianthus tuberosus, Ambrosia artemisifolia var. elatior, Xanthium strumarium, Erigeron annuus, Erigeron canadensis, Conyza sumatrensis, Senecio vulgaris, Bidens frondosa, Tagetes minuta, Taraxacum officinale, Taraxacum laevigatum and Sonchus oleraceus.

Application of the Proper Air Supply Amount Based on the Influent Water Quality for the Development of Efficient Blower Control Logic in Sewage Treatment Plants (하수처리장의 효율적인 Blower Control Logic 개발을 위한 유입수질 기반 공기공급량 적용 연구)

  • Yeo, Wooseok;Kim, Jong Kyu
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.42 no.4
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    • pp.493-499
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    • 2022
  • The standards pertaining to the quality of discharged water in sewage treatment plants are strengthening, and accordingly, facilities in sewage treatment plants are being upgraded. In addition, the discharge water quality of sewage treatment plants must be maintained at a high level, and efficient sewage treatment plant operations have thus emerged as a very important issue. For the efficient operation of sewage treatment plants, this study applied a basic blowing amount calculation method based on sewage facilities to evaluate the required oxygen amount and blowing amount according to inflow water quality by logicizing various influencing factors. As a result of calculating the amount of air blown by applying actual April water quality data from sewage treatment plant A to the blower demand calculation developed through this study, it was found that the average amount of air blown was reduced by about 12%. When the blower demand calculation developed here is applied to an actual sewage treatment plant, the amount of air blown can be controlled based on the inflow water quality. This can facilitate the realization of an autonomous control of sewage treatment plants, in contrast to the existing sewage treatment operation method that relies on operational experience of operator. In addition, it is expected that efficient sewage treatment plants can be operated by reducing blowing amounts and power costs, which will contribute to both energy and carbon savings.

Tissue Culture of Stone Fruit Plants Basis for Their Genetic Engineering

  • Csanyi, Marta;Wittner, Anita;Nagy, Agenes;Balla, Ildiko;Vertessy, Judit;Palkovics, Laszlo;Balazs, Eevin
    • Journal of Plant Biotechnology
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    • v.1 no.2
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    • pp.91-95
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    • 1999
  • Genetic engineering of stone fruit species like apricot, plum, peach and cherry are hampered by the inefficient and low-level regeneration processes in tissue culture. The first transgenic stone fruit species have emerged from transformed hypocotyls. These great achievements were applauded by the scientific community contrary the fact that hypocotyl derived transgenic plants have no real brooding value. Tissue culture of different organs of valuable cultivars are recorded with an extremely low-level of regeneration in the literature. To improve the tissue culture basis of stone fruit plants an extensive tissue culture programme were launched and dozens of different media were compared including a series of hormone concentration in the tissue culture systems. Our continuous efforts were crowned by a very efficient method for achieving up to 30-40% regenerable petioles. Usually on a single petiole several well-separated meristems were induced. After 3-4 weeks of cultivation shoots were developed. The basic media $K_2$ were supplemented with 10g/L saccharose, 10g/L glucose and 10g/L maltose. The following plant hormones were used BAP 1mg/L, TDZ 1mg/L, 2-iP 1mg/L and IAA 0,1 mg/L concentrations. The Petri dishes were kept for 3 weeks in dark at a temperature 22$^{\circ}C$ for 8 hours and 22-24$^{\circ}C$ for 16 hours. The Petri dishes were sealed with Parafilm. The regeneration of the petioles were genotype independent and we were able to regenerate different plum cultivars with almost the same efficiency.

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Life History of Locastra muscosalis (Walker) (Lepidoptera: Pyralidae) and Its Natural Enemies (벼슬집명나방의 생활사 및 천적 종류)

  • 박철하;이범영;이세표
    • Korean journal of applied entomology
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    • v.32 no.1
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    • pp.101-104
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    • 1993
  • The life history and host plants of Locastra muscosalis (Walker) which is a defoliating pest of walnut trees were studied mainly in Chungchongbuk-do province. Juglans nigra Linne, J. mandshurica Mixim., Carya illinoensis koch and Pterocarya stenoptera DC. were found to be new host plants. Locasta muscosalis (Walker) had one generation per year and the adults emerged form late June to late July with a peak emergence around July 10th. Females oviposited a mean of 560 eggs on the top surfaces of leaves. The duration of the egg stage was from 7 to 12 days. Young larvae fed on the leaves within webs that bound the leaves beginning in the middle of July. In the middle of September the fully matured larvae entered the soil -a cm below the soil surface, and the pupal period lasted 16 days on average. The natural enemies observed and/or reared from larvae of pupae were 3 species of parasitoids, 6 species of predators and an unidentified virus.

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